In typical clothes washing machines, there is provided a clothes receiving receptacle such as a perforate basket or tub within which is disposed an agitator, the agitator oscillated to produce the clothes washing action. Such agitator generally consists of a center post extending upwardly into the receptacle with vanes from the center post extending radially outward on a lower bell portion of the agitator.
Such agitators do not for the most part exhibit good turnover capability, i.e., the ability to create a toroidal circulation of the clothes due to the generally mediocre performance of such agitators in forcing the clothes downwardly along the center post.
There has thus heretofore been provided a variety of arrangements for producing a vertical movement of an impeller or agitator which tends to force the clothes downwardly into the receptacle in the center region of the basket and to set up the toroidal motion and consequent turnover of the clothes.
This turnover motion is desirable for good washing action inasmuch as it presents varying clothes surfaces for scrubbing action against each other and the surfaces of the basket and the agitator. In addition, the rollover allows the heavy solid particles to be settled out and collected in the lower region of the tub or basket.
In some washing machines, the agitator consists of an agitator mechanism in which tapering skirt elements are caused to be reciprocated. Such skirt elements are generally frusto-conical in shape and may be upwardly or downwardly directed and are caused to be reciprocated by a relatively complex transmission. Such machines are normally less durable and reliable than oscillating agitators, and tend to be more costly to manufacture.
Examples of these machines are disclosed in U.S. Pat. Nos. 2,584,291; 3,010,303; 3,197,791; 3,245,235 and 3,648,487.
In U.S. Pat. No. 3,678,714, there is disclosed an arrangement whereby a conventional oscillating agitator is provided with a reciprocating agitator device on the upper region of the agitator post, which reciprocation is produced by the oscillation of the agitator by a cam arrangement affixed to the basket to be relatively stationary during oscillation of the agitator, with the interreaction of the relatively stationary cam and a cam carried by the reciprocating mechanism resulting in vertical reciprocation of an agitator element, thereby improving the rollover characteristics of the agitation action.
While this is simpler than the aforementioned vertical reciprocation type washing machines, this arrangement is still relatively complex and a costly addition to the machine.
Accordingly, it is an object of the present invention to provide an agitator mechanism which affords good turnover agitation action without entailing complex mechanical components in order to achieve vertical reciprocation of an agitator element.
It is another object of the present invention to provide an agitation mechanism which is readily utilized in conjunction with a conventional oscillating agitator having radially extending vane portions thereon, or which may be employed without such conventional vaning.